YEN BAI AIRFIELD (UNDER CONSTRUCTION) YEN BAI, NORTH VIETNAM

• Document Type: CREST
• Collection: NGA Records (Formerly NIMA)
• Document Number (FOIA) /ESDN (CREST): CIA-RDP79-00849A001100070008-7
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 5
• Document Creation Date: December 28, 2016
• Document Release Date: March 9, 2006
• Sequence Number: 8
• Publication Date: January 11, 1968
• Content Type: REPORT

ATTAbHP4IIeIT TO L- 4696
ll JANUARY 1968
PAGE 1
YEN BAI AIRFIELD (UNDER CONSTRUCTION
YEN BAIL NORTH VIETNAM
2143N 1045]E
1. SIGNIFICANCE:
ACTIVITY AT YIIV BAI AIRFIELD.
2. LOCATION:
THE AIRFIELD IS LOCAT"rD 1.7 NM NORTHWEST OF YEN BAI,
3. BACKGROUND:
PHOTOGRAPHY OF THIS AREA IN LATE AUGUST 1965 REVEALID ONLY ISOLATED
AREAS OF DWELLIlVG AND RICE PADDIES ALONG THE HIGHWAY FARAT~T~~~ Tb THE HA NOI~
NORTH OF THE RED RIVER, THREE ROAD SEGMENTS LEADIlVG FROM THE MAIN ROAD
APPEARED TO BE UNDER CONSTRUCTION.
PHOTOGRAPHY OF NOVEMBER 1965 Rr,~AT,Fn A SIGNIFICtL'VT INCREASE IN CON-
STRUCTION ACTIVITY. A MINOR EFFORT HAD ADDED TWO HUNDRED AND THREE NEW
BUILDINGS WITHIN TI~,IMMEDIATE AREA, THEY APPEARED TO BE BARRACKS OR
STORAGE-TYPE BUILDINGS AND WERE NOT CONSISTENT WITH THE INDIGENOUS VIET-
NAMESE CONSTRUCTION.
PLACE IN AN ATTEMPT TO LEVEL AND FILL THE PREDOMINATELY KARST TERRAIN. TWO
LARGE AND SEVERAL MINOR CANALS HAD BEEN CONSTRUCTED ADJACENT TO THE ,AREA OF
EARTH MOVING ACTIVITY. SIXTEEN NEW AW SITES FIFTY-FOUR NEW BUILDINGS AND
These notes have been prepared for briefing purposes only and should not be used for detailed analyllcal work. Their use
should be restricted to the particular briefing board(s) they were prepared for and must be considered valid only for the re~
porting period as indicated by the date of issue. Far information concerning these notes contact Chief, Collateral Support
Division, NPIC.
 A~pYoved For Release 2006/ 4~'fiQUtfJ100070008-7 E"'_"'^"~
(c) NATIONAL PHOTOGRAPHIC INTERPRETATION CENTER
ATTACHMENT TO L-4696
11 JANUARY. 1968
PAGE 2
PHOTOGRAPHY OF MARCH 1966 REVEALED THE EMERGENCE OF AN EXTENSIVE
DRAIlVAGE PATTERN. INDIVIDUAL REVEZMIIVTS AND REVETTED TRUCK PARKS HAD
BEIIV BUILT ON THE CONSTRUCTION SITE ITSELF. AN OPE1V STORAGE AREA WAS
OBSERVED.ADJACENT TO THE ACTICITY AND NUMEROUS PIECES OF CONSTRUCTION
EQUIPMENT WERE OBSERVED WITHIN THE AREA.
PHOTOGRAPHY OF APRIL 1966 INDICATED THAT THE CONSTRUCTION ACTIVITY
WAS NOW CENTERED ALMOST EXCLUSIVELY ON LEVELING AND FILLING THE TERRAIN
IN ONE PARTICULAR AREA. THE PHOTOGRAPHIC COVERAGE FROM AUGUST THROUGH
DECEMBER 1965 HAD INDICATED THAT THE PRIMARY EFFORT WAS TO DEVELOP GOOD
LOGISTICAL SUPFURT BY DEVELOPING AN ADEQUATE ROAD SYSTEM AS WELL AS
ADEQUATE STORAGE AND SUPPORT FACILITIES. THE APRIL COVERAGE INDICATED-.
A PHASING OUT OF THIS AS A PRIME ACTIVITY WITH FEW NEW ROAD EXTENSIONS OR
NEW .BUILDINGS OBSERVED SINCE DECEMBER. THE NEW PHASE CENTERED AROUND THE
LEVELING OF THE TERRAIN, ALONG WITH THE ENLARGEMENT AND EXTENSION OF THE
ALREADY DEVELOPING DRAINAGE SYSTEM.
PHOTOGRAPHY OF JUNE 1966 REVEALED THAT NEW EARTH MOVING ACTIVITY HAD
ENLARGED THE PREVIOUS AREA UNDER CONSTRUCTION TO APPROXIMATELY 10,500 X
950 FT, ORIENTED ZN A NW~SE DIRECTION, AND INCLUDED ROADS AT BOTH ENDS OF
THE RUNWAY.
ALSO OBSERVED WAS A LARGE STORAGE COMPLEX, COVERING AN AREA OF APPRO-
XIMATELY THREE SQUARE NAUTICAL MILES, IPM4EDIATELY NORTHEAST OF THE CONSTRUC-
TION AREA, INDICATIONS WERE THAT THIS AREA WAS BEING USED PRIMARILY FOR
These notes have been prepared for briefing purposes only and should not 6e used far detailed analytical worN. Their use
should be restricted to the Darticular briefing board(s) they were prepared for and must be considered valid only far the re~
porting period as indicated by the date of issue. For information concerning these notes contact Chiet, Collateral Support
Division, NPIC.
Approved For Release 2006/03/16 :CIA-RDP79-0~~11 0070008-7
 REFERENCE: ATTACHMENT TO L-4696
11 JANUARY 1968
PAGE 3
WORKER'S HOUSING AND THE STORAGE OF CONSTRUCTION MATERIALS AND EQUIPNNIEINT,~
A TOTAL OF SEVEN HUtVDRED AND NINETEEN BUILDINGS WERE OBSERVED WITHIN THE
AREA OF INTEREST AT THIS TIME.
PHOTOGRAPHY OF MAY 1967 REVEALED NO CHANGE IN THE OVERALL DIMEtVSIONS
AND ORIEtVTATION OF THE AIRFIELD. THE HILL PREVIOUSLY'OBSERVED IN THE,
CENTER OF THE AIRFIELD HAD BEEN LEVELED AND THE ROAD NETWORK SERVING THE
AIRFIELD HAD BEEN COMPLETED. AT LEAST SEVENTY PIECES OF CONSTRUCTION
EQUIPMIIJT WAS OBSERVED. THE DRAINAGE SYSTEM APPEARED COMPLETE AND IN
OPERATION. DEFENSES AROUND THE AIRFIELD INCLUDED OCCUPIED LIGHT AAA SITES,
TRENCHES, AND FOXHOLES.
4. MISSION READOUT:
CONSTRUCTION ACTIVITY AT YEN BAI AIRFIELD. THE OVERALL DIlHIIPSIONS OF THE
AIRFIELD HAVE NOT CHANGED AND REMAIN APPROXIMATELY 10,500 X 950 FT. WITH
APPROXIMATE RUNWAY DII~NSIONS OF 7,200 X 125 FT. THE FOLLOWING ACTIVITY
INDICATES THAT THE NORTH VIETNAMESE ARE TRYING TO COMPLETE THE AIRFIELD AS
RAPIDLY AS POSSIBLE: CONTIIVUING PROBABLE CONCRETE SURFACING ACTIVITY ON
THE RUNWAY, TAXIWAY, AND CROSSOVER LINKS; CONSTRUCTION OF TEN AIRCRAFT
REVE'II~VTS (FIVE AT EACH END OF THE RUNWAY; CONTIlVUIIVG IMPROVEMENT AND
CONSTRUCTION OF THE ROAD NETWORK IN AND AROUND THE AIRCRAFT DISPERSAL AREA
AT THE NORTHWEST END OF THE RUNWAY;.AND, CONSTRUCTION OF THIRTEEN AIRCRAFT
REVETMENTS IN THE DISPERSAL AREA.
These notes have been prepared for briefing purposes only and should not be used for detailed analytical work. Their use
should he restricted to the particular briefing board(s) they were prepared for and must be considered valid only for the re~
porting period as indicated by the dale of issue. For information concerning these notes contact Chief, Collateral Support
Niuisioq NPIC.
Approved For Release 2006/03/16 :CIA-RDP79-O~Q~1 100070008-7
 r
~App~oved For Release 2006/
ATPACHMENT TO L- 4696
11 JANUARY 1968
PAGE 4
TWO BOA'ID CRATERS IN THE RUNWAY SURFACE AND MINOR DAMAGE TO THE
ADJACENT AREA ARE THE RESULT OF U.S. AIR STRIKES; HOWEVER: THE AIR
STRIIO;S HAVE NOT SLOWED THE. RATE OF CONSTRUCTION ACTIVITY WHICH IS
EVIDENCED BY THE REPAIR OF BOMB CRATERS ON THE RUNWAY.
NU[vIEROUS OCCUPIED AAA flOSITIONS ARE ALSO OBSERVED,
These notes have keen prepared for briefing purposes only and should not be used for detailed analytical worX. their use
should be restricted to the particular briefing board(s) they were prepared for and must be considered valid only for the re~
porting period as indicated by the date of issue. For information concerning these notes contact Chief, Collateral Support
~ivisian, NPIC.
Approved For Release 2006/03/16 :CIA-RDP79-O5~ 1~~1100070008-7
 i4ppfoved For Release 2006/03/16 :CIA-R P79-00849A00110007 008-7
(c) NATIONAL PHOTOGRAPHIC INTERPRETATION CENTER
ATTACHI~NT TO L-4696
11 JANUARY 1968
COPY 2 - CIA~OSA (ATTN:
COPY 3 -CSD~NBB~SEAS
These notes have been prepared for briefing purposes only and should not be used for detailed analytical work. Their use
should be restricted to the particular briefing board(s) they were prepared for and must be considered valid only for the re~
porting period as indicated by the date of issue. For information concerning these notes contact Chief, Collateral Support
Division, NPIC.
Approved For Release 2006/03/16 :CIA-RDP79-Ob~b1100070008-7
PREPARED BY: NPIC~CSD
DISTRIBUTION:
COPY 1 - DIA (ATTN